/*
 Slimbox v1.3 - The ultimate lightweight Lightbox clone
 by Christophe Beyls (http://www.digitalia.be) - MIT-style license.
 Inspired by the original Lightbox v2 by Lokesh Dhakar.
 */

var Lightbox = {

  init: function(options) {
    this.options = Object.extend({
      resizeDuration: 400,
      resizeTransition: Fx.Transitions.sineInOut,
      initialWidth: 200,
      initialHeight: 200,
      animateCaption: true
    }, options || {});

    this.anchors = [];
    $each(document.links, function(el) {
      if (el.rel && el.rel.test(/^lightbox/i)) {
        el.onclick = this.click.pass(el, this);
        this.anchors.push(el);
      }
    }, this);

    this.eventKeyDown = this.keyboardListener.bindAsEventListener(this);
    this.eventPosition = this.position.bind(this);

    this.overlay = new Element('div').setProperty('id', 'lbOverlay').injectInside(document.body);

    this.center = new Element('div').setProperty('id', 'lbCenter').setStyles({width: this.options.initialWidth+'px', height: this.options.initialHeight+'px', marginLeft: '-'+(this.options.initialWidth/2)+'px', display: 'none'}).injectInside(document.body);
    this.image = new Element('div').setProperty('id', 'lbImage').injectInside(this.center);
    this.prevLink = new Element('a').setProperties({id: 'lbPrevLink', href: '#'}).setStyle('display', 'none').injectInside(this.image);
    this.nextLink = this.prevLink.clone().setProperty('id', 'lbNextLink').injectInside(this.image);
    this.prevLink.onclick = this.previous.bind(this);
    this.nextLink.onclick = this.next.bind(this);

    this.bottomContainer = new Element('div').setProperty('id', 'lbBottomContainer').setStyle('display', 'none').injectInside(document.body);
    this.bottom = new Element('div').setProperty('id', 'lbBottom').injectInside(this.bottomContainer);
    new Element('a').setProperties({id: 'lbCloseLink', href: '#'}).injectInside(this.bottom).onclick = this.overlay.onclick = this.close.bind(this);
    this.caption = new Element('div').setProperty('id', 'lbCaption').injectInside(this.bottom);
    this.number = new Element('div').setProperty('id', 'lbNumber').injectInside(this.bottom);
    new Element('div').setStyle('clear', 'both').injectInside(this.bottom);

    var nextEffect = this.nextEffect.bind(this);
    this.fx = {
      overlay: this.overlay.effect('opacity', {duration: 500}).hide(),
      resize: this.center.effects({duration: this.options.resizeDuration, transition: this.options.resizeTransition, onComplete: nextEffect}),
      image: this.image.effect('opacity', {duration: 500, onComplete: nextEffect}),
      bottom: this.bottom.effect('margin-top', {duration: 400, onComplete: nextEffect})
    };

    this.preloadPrev = new Image();
    this.preloadNext = new Image();
  },

  click: function(link) {
    if (link.rel.length == 8)
      return this.show(link.href, link.title);

    var j, imageNum, images = [];
    this.anchors.each( function(el) {
      if (el.rel == link.rel) {
        for (j = 0; j < images.length; j++)
          if(images[j][0] == el.href)
            break;
        if (j == images.length) {
          images.push([el.href, el.title]);
          if (el.href == link.href)
            imageNum = j;
        }
      }
    }, this);

    return this.open(images, imageNum);
  },

  show: function(url, title) {
    return this.open([[url, title]], 0);
  },

  open: function(images, imageNum) {
    this.images = images;
    this.position();
    this.setup(true);
    this.top = window.getScrollTop() + (window.getHeight() / 15);
    this.center.setStyles({top: this.top+'px', display: ''});
    this.fx.overlay.start(0.8);
    return this.changeImage(imageNum);
  },

  position: function() {
    this.overlay.setStyles({top: window.getScrollTop()+'px', height: window.getHeight()+'px'});
  },

  setup: function(open) {
    var elements = $A(document.getElementsByTagName('object'));
    if (window.ie)
      elements.extend(document.getElementsByTagName('select'));
    elements.each( function(el) {
      el.style.visibility = open ? 'hidden' : '';
    });

    var fn = open ? 'addEvent' : 'removeEvent';
    window[fn]('scroll', this.eventPosition)[fn]('resize', this.eventPosition);
    document[fn]('keydown', this.eventKeyDown);
    this.step = 0;
  },

  keyboardListener: function(event) {
    switch (event.keyCode) {
      case 27:
      case 88:
      case 67:
        this.close();
        break;
      case 37:
      case 80:
        this.previous();
        break;
      case 39:
      case 78:
        this.next();
    }
  },

  previous: function() {
    return this.changeImage(this.activeImage-1);
  },

  next: function() {
    return this.changeImage(this.activeImage+1);
  },

  changeImage: function(imageNum) {
    if (this.step || (imageNum < 0) || (imageNum >= this.images.length))
      return false;
    this.step = 1;
    this.activeImage = imageNum;

    this.bottomContainer.style.display = this.prevLink.style.display = this.nextLink.style.display = 'none';
    this.fx.image.hide();
    this.center.className = 'lbLoading';

    this.preload = new Image();
    this.preload.onload = this.nextEffect.bind(this);
    this.preload.src = this.images[imageNum][0];
    return false;
  },

  nextEffect: function() {
    switch (this.step++) {
      case 1:
        this.center.className = '';
        this.image.style.backgroundImage = 'url('+this.images[this.activeImage][0]+')';
        this.image.style.width = this.bottom.style.width = this.preload.width+'px';
        this.image.style.height = this.prevLink.style.height = this.nextLink.style.height = this.preload.height+'px';

        this.caption.setHTML(this.images[this.activeImage][1] || '');
        this.number.setHTML((this.images.length == 1) ? '' : 'Image '+(this.activeImage+1)+' of '+this.images.length);

        if (this.activeImage)
          this.preloadPrev.src = this.images[this.activeImage-1][0];
        if (this.activeImage != (this.images.length - 1))
          this.preloadNext.src = this.images[this.activeImage+1][0];
        if (this.center.clientHeight != this.image.offsetHeight) {
          this.fx.resize.start({height: this.image.offsetHeight});
          break;
        }
        this.step++;
      case 2:
        if (this.center.clientWidth != this.image.offsetWidth) {
          this.fx.resize.start({width: this.image.offsetWidth, marginLeft: -this.image.offsetWidth/2});
          break;
        }
        this.step++;
      case 3:
        this.bottomContainer.setStyles({top: (this.top + this.center.clientHeight)+'px', height: '0px', marginLeft: this.center.style.marginLeft, display: ''});
        this.fx.image.start(1);
        break;
      case 4:
        if (this.options.animateCaption) {
          this.fx.bottom.set(-this.bottom.offsetHeight);
          this.bottomContainer.style.height = '';
          this.fx.bottom.start(0);
          break;
        }
        this.bottomContainer.style.height = '';
      case 5:
        if (this.activeImage)
          this.prevLink.style.display = '';
        if (this.activeImage != (this.images.length - 1))
          this.nextLink.style.display = '';
        this.step = 0;
    }
  },

  close: function() {
    if (this.step < 0)
      return;
    this.step = -1;
    if (this.preload) {
      this.preload.onload = Class.empty;
      this.preload = null;
    }
    for (var f in this.fx)
      this.fx[f].stop();
    this.center.style.display = this.bottomContainer.style.display = 'none';
    this.fx.overlay.chain(this.setup.pass(false, this)).start(0);
    return false;
  }

};

window.addEvent('domready', Lightbox.init.bind(Lightbox));